When you meet someone who has just published a book you usually congratulate them. It’s an achievement to write any book. But today, with the comedian and writer Anne Gildea, that would sound wrong. Her book is called I’ve Got Cancer, What’s Your Excuse? A Journey Through Black Dog Days, the Big C and Laughter. It wouldn’t exist without a horrible, life-changing experience, so congratulations seem inappropriate.

In July 2011 Gildea was diagnosed with advanced breast cancer. She was treated, then had a mastectomy and reconstructive surgery. She has since received “the best possible prognosis I could have got”, she says, smiling with relief.

Gildea was also filmed for Breast Cancer: No Laughing Matter, last year’s RTÉ programme following her through treatment. The documentarymakers contacted her at about the same time that Hachette Ireland, the publisher, asked her to write a memoir based around her illness.

“I wrote the book because I was asked,” Gildea says, adding that she’s not arrogant enough to have written it as a guide for someone going through cancer, but “I know that when I was going through breast cancer I would have loved to have read something like this, to know that this is what it feels like, this is what it smells like, this is what the nausea feels like, this is the emotional and physical reality of having a mastectomy. What interested me was the texture of the experience.”

Twice she almost gave up writing the book, which she started after finishing radiotherapy. The publisher had wanted it in five months, but it took her 14.

“I had to totally re-engage with the process, and it was so hard,” she says. “It was very painful to go back to what I was feeling then. It’s not healthy. It was very hard to write the book, but overall it was therapeutic.”

The NualasWhat kept her going through treatment was keeping life as normal as possible. She worked with her fellow Nualas comedians Sue Collins and Maria Tecce for as long as she could, and she wrote a newspaper column. It’s business as usual again from September 6th, when the Nualas start an autumn tour of the country, beginning at the Civic Theatre in Tallaght.

As a performer she has used aspects of life as material in the past. With the publication of the book she has now shared her experience both in print and on broadcast media. Has sharing the experience so publicly been difficult? “I told my brother the other day I was going to have a colonoscopy, and he said, ‘When is that being broadcast?’

“Nobody close to me wanted me to do the documentary,” she says. “They felt I was vulnerable. My brother and sister are discreet people, and they thought that it was a very indiscreet project and that the most important thing going through treatment was to engage with it and not get stressed by anything else.

“But, frankly, doing the documentary filled up a space I used to wish could be filled up by a partner. It made it less lonely, because I didn’t have a partner and kids and stuff.”

The book went through four drafts. “It was very hard to get the tone right,” she says. “The first draft was insane. It was so angry. It was very dark. If it had been a painting it’d be a load of muddy oils.”

Why was it so angry? There is a long silence. Gildea’s book is not only a visceral account of breast cancer but also, in part, an examination of early family life.

She writes of being uprooted from suburban Manchester at five to a dilapidated inherited farmholding in rural Co Sligo. “I was raised in a glorified shed,” she puts it in the book. “The notion of home never came into it.”

“The anger was about things in the past,” she answers eventually. “There are sentences in the book that were originally 7,000-word chapters about childhood.”

One of them is this: “I regularly recalled something my father repeated throughout our childhood, that we, my brother, sister and I, were nothing but financial liabilities.”

The chapters about her early life make for uncomfortable reading. You can see shadows in the text but not what those shadows conceal. It’s as if she was undecided about how much to reveal of the “four damp-dripping, crumbling walls of that hated house” that “contained an unravelling of family.”

In fact I’ve Got Cancer, What’s Your Excuse? is really two books: the account of her illness and a devastating sliver of unfinished memoir.

“The first thing I thought about when I got my diagnosis was that house,” she says. “It’s been the core motif of my life. All my life I’ve had nightmares about the house I grew up in.”

She says she didn’t write in more detail about those early years because she didn’t want to hurt anyone. The struggle between the desire to tell her story and the desire not to alienate her family is evident in the text.

Neither of her siblings has read the whole book. “They were both very worried about it, so I kept pulling back and pulling back about the early stuff.”

The book is dedicated to her parents, neither of whom has yet read it either. “I’ll send my mum a copy. She lives in England. I’ll send my dad a copy, too, but will he read it? I don’t know if he’ll be really interested. I dedicated it to them because I think that my parents’ greatest gifts to me were my siblings.”